Fix spelling and grammar

- No need to escape single or double quotes in source examples (improves readability of code snippets in HTML files)
- Typography: Use … (horizontal ellipsis) instead of ...
- Typography: Use Apostrophe (’) instead of single quote in texts
- Always capitalize Dalek (as a name) and acronyms (HTML, JSON, etc.)
- Fixed typos and gramattical issues
Initially build minified CSS before running the watch task for the first time